1. Field of the Invention
This invention relates to metal raceway constructions having independent cells for separate delivery of three types of utilities, such as electrical wires, to a single location in such a fashion as to facilitate ease of access to electrical utility lines.
2. Description of the Prior Art
The advantageous use of formed metal deck in combination with concrete in establishing floors and roofs for buildings and the like has long been known. In general, in such constructions an elongated metal deck member is provided with alternating ribs and valleys. The deck member is connected to associated deck members and is supported by suitable structural beams and the like. A layer of overlying concrete is poured onto the deck. When the concrete hardens, a composite action is created wherein the resultant structure has excellent tensile strength as a result of the metal deck and excellent compressive strength as a result of the presence of concrete.
In connection with such constructions it has been known to provide a sheet underlying the ribbed deck in order to define a series of elongated cells or raceways permitting passage of supply means for various utilities through such cells.
Among the utilities which pass through raceways are electrical wires provided for various purposes.
It has been known, in connection with general building construction concepts to provide divided compartments in walls or floors so as to separate different types of electrical supply from each other. See for example, U.S. Pat. Nos. 1,718,253; 2,000,243 and 3,793,793.
It has been known to provide under a concrete floor member, metal duct systems which contain or are adapted to contain electrical wires and are reached through the making of a hole in the duct system. See, for example, U.S. Pat. Nos. 2,073,490; 3,303,264; 3,592,956 and 3,721,051.
It has been known to provide holes in the sidewalls of adjacent rib members so as to permit access to wires through a valley disposed between the ribs. See, for example, U.S. Pat. Nos. 3,426,492 and 3,426,802.
U.S. Pat. No. 3,886,702 discloses a bottomless electrical cable trench wherein access is provided to certain wires through either openings in the top of a rib or in the sidewall.
U.S. Pat. No. 3,459,875 discloses, in one embodiment, access to multiple wires through bridging conduits connecting ribs and openings in the top of a rib or in another embodiment combinations of bridging conduits and sidewall openings.
U.S. Pat. No. 3,701,837 discloses access to electrical wires through two, rib-top openings and a valley containing a wire.
It has also been suggested to provide coverings for portions of the valley between two ribs in connection with provision of access to utility lines. See, for example, U.S. Pat. Nos. 3,417,191; 3,903,666; 3,932,696; 4,194,332 and 4,232,493.
It has also been known to provide a separate, elongated partitioned chamber interposed between deck sections and divided into three passageways. Access to each passageway is obtained by top entry through an overlying enclosure. An electrical receptacle is disposed within the enclosure. See Mac-Fab Products, Inc. Catalog MF-520. Such a construction requires use of a specially configurated separate chamber and employs top access to the partitioned passageways.
It has also been known to subdivide a chamber into three compartments by means of upwardly projecting walls formed within a lower panel of a separate elongated member adapted to be interposed between deck sections. An overlying enclosure is partially received within a recess in the upper panel and communicates with the three compartments through openings in the formed upper panel. An electrical receptacle is centrally disposed within the enclosure. Not only does this structure require the use of integrally formed compartment-defining partitions in the lower panel, but also access to the lateral compartments though effected in part through the upper panel formed sidewall is severely restricted.
In spite of the hereinbefore recited evolution of the art, there remains a very real and substantial need for a system which will permit separate housing within a deck assembly of three types of electrical supply such as telephone, power and signals such as computer lines, for example, while permitting convenient and complete access to all three sources at a single location in the construction.